1. Field of the Invention
The present invention relates to a fuel reformer, and more particularly, to a fuel reformer for generating thermal energy through an oxidation reaction of a fuel.
2. Description of the Related Art
A fuel cell is constructed as a system for generating electric energy using a fuel.
In the fuel cell, a polymer electrolyte membrane fuel cell has an excellent output characteristic, a low operating temperature, and fast starting and response characteristics. In addition, the polymer electrolyte fuel cell advantageously has a wide range of applications including a mobile power source for vehicles, a distributed power source for home or buildings, and a small-sized power source for electronic apparatuses.
The fuel cell system employing the polymer electrolyte membrane fuel cell includes a fuel cell main body, which can also be referred to as a stack, a fuel reformer which reforms the fuel to generate a reforming gas containing hydrogen and supplies the reforming gas to the fuel cell main body, and an oxidant gas supply unit which supplies an oxidant gas to the stack.
Therefore, the polymer electrolyte membrane fuel cell system generates electric energy in the stack through an electro-chemical reaction between the reforming gas supplied from the fuel reformer and the oxidant gas supplied from the oxidant gas supply unit.
The fuel cell reformer may include a heat source which generates thermal energy by oxidizing a fuel using an oxidation catalyst and a reforming reaction unit which generates the reforming gas through a reforming reaction of the fuel using the thermal energy.
Here, the heat source can generate the thermal energy by oxidizing a liquid fuel such as methanol and ethanol or a gaseous fuel such as LPG and LNG. Particularly, the heat source using the liquid fuel can generate the thermal energy in a certain (or predetermined) temperature range through the oxidation reaction of the fuel using the oxidation catalyst even at room temperature.
On the other hand, because the heat source cannot generate the oxidation reaction of the gaseous fuel using the oxidation catalyst at room temperature, when a conventional fuel reformer includes the heat source that oxidizes a gaseous fuel, an additional preheater is needed for preheating the oxidation catalyst to a certain (or predetermined) temperature to enable an oxidation reaction of the gaseous fuel.
In addition, a conventional fuel reformer includes a heat source that ignites and burns a liquid fuel; and because the energy efficiency of a fuel reformer is changed by the location of the heat source, and the heat source is oxidized by the flame, the durability of the heat source deteriorates as a result. Thus, the heat source has to be frequently replaced, thereby reducing the lifespan of the fuel reformer.